We just realised that Ruy Ribeiro and Sebastian Bonhoeffer published an article in 1999 in AIDS, where they study the importance of the timing of treatment for HIV. Ribeiro and Bonhoeffer use a target cell limited model but reach a conclusion similar to us (treatment should be not be given too early to minimise the evolution of drug resistance).
Ribeiro, R.M. & Bonhoeffer, S. 1999. A stochastic model for primary hiv infection: optimal timing of therapy. AIDS 13: 351–7.